Demands for higher data rates for mobile services are steadily increasing. At the same time, modern mobile communication systems as 3rd Generation systems (3G) and 4th Generation systems (4G) provide enhanced technologies, which enable higher spectral efficiencies and allow for higher data rates and cell capacities. As operators are seeking to extend the coverage of their networks, relaying concepts become more and more sophisticated.
In the 3rd Generation Partnership Project (3GPP) as international standardization body, relay architectures for Evolved-Universal Mobile Telecommunication System (UMTS) Terrestrial Radio Access (E-UTRA) have been discussed and results can be found, for example, in Technical Recommendation (TR) 36.806 or TR 36.814. These new architectures are likely to be established in the future for Long Term Evolution—Advanced (LTE-A) networks.
In relaying architectures a relay station transceiver may extend the coverage of a base station transceiver. Basic concepts use a relay station transceiver, which receives signals from a base station transceiver and forwards them to mobile transceivers, and vice versa, for example, as a repeater in an amplify-and-forward fashion. Other relaying concepts may receive the signals from the base station transceivers at the relay station and demodulate or decode them before they are re-encoded or re-modulated and forwarded to the mobile transceiver, and vice versa. The radio signals from the base station transceiver are received, amplified and transmitted to the mobile transceiver, from the mobile station transceiver, respectively. In such a scenario the relay station may not even be identified as such by a mobile transceiver. In other concepts, the relay station transceiver may correspond to a base station transceiver, which is connected to another base station transceiver, the so-called donor base station transceiver, via a radio interface and provides radio services as a base station to the mobile transceiver station. The base station transceiver then forwards data for transmission to the relay station transceiver through backhaul signaling, which can generally be implemented in a wireless manner.